When a person stop breathing, it is imperative that effective ventilation be instituted as soon as possible. A blade laryngoscope is commonly employed to place an ETT (endotracheal tube) into a person's trachea. However, a blade laryngoscope has significant patient risks. These include dental injury, airway soft tissue injury, and further injury to a patient's with a neck injury caused by neck manipulation during blade insertion. Further, visualization of vocal cords can be difficult or impossible. A result can be an endotracheal tube that is misguided into a patient's esophagus. Such improper intubation, if not quickly corrected can have fatal consequences.
There are many other supraglottic airway (SGA) devices being used in the spontaneous breathing of anesthetized patients, during recovery from anesthetics, weaning of some patients in intensive care unit, or for airway management during resuscitation. Examples of prior art devices include but are not limited to supraglottic ventilation devices, Ballooned Oro-pharyngeal airway, LMA, and Combi-tube devices.
There are many prior art devices used in endotracheal intubation. These include metal Macintosh and Miller laryngoscope blade, many types of video larynscopes such as the Glidescope, Mcgrath, Airtraq, C-Mac, Berci-Kaplan DCI, Pentax Airway Scope, Truview EVO, and LMA fast track. These devices rely on obtaining direct or indirect view of the epiglottis and glottis inlet during intubation. However, a variety of trauma and clinical settings can make direct or indirect visual observation very difficult if not impossible. These include an unstable cervical spine injury, airway bleeding or heavy secretion, an obese patient, or a patient that needs intubation in an unusual position such as a person in a car wreck.
Recently, there are devices introduced for blind placement of an endotrachecal tube. Examples of these include a laryngeal mask airway (LMA), U.S. Pat. No. 4,509,514 in 1985 by Brain and an intubation laryngeal mask airway (ILMA), U.S. Pat. No. 5,303,697 1994 by Brain. However, these LMA blind intubation devices are easily positioned incorrectly. Even when ventilation can still be carried out, an LMA can be inefficient and increase the risk of aspiration. Further, even when this blind intubation device is correctly inserted and positioned, sliding an endotracheal tube alone the elongated air tube into a trachea is difficult. Another problem with these devices is that the device can push or catch the epiglottis moving it over the glottis and obstruct the airway. Another disadvantage of an LMA is that it often poorly seals making it easier for regurgitation and aspiration.
IMLA was especially designed for blind intubation. One ILMA patent, U.S. Pat. No. 5,896,858 by Brain 1999, was designed to insert an endotracheal tube though an LMA without visualization. This design has achieved limited acceptance and has a number of limitations.
First, the ILMA has a metal handle with a pronounced curved region making it difficult to insert into a patient's mouth. It usually requires muscle relaxants drugs in order to open a patient's mouth wide enough to prevent tissue damage. Second, the ILMA relies on precise positioning and perfect alignment of the epiglottis with the recessed epiglottis elevation bar so that the epiglottis elevation bar would raise the epiglottis out of the way of an advancing endotracheal tube. Such precise position is often hard to achieve. One problem that the ILMA can exhibit is that the tip can become folded at the back of the oropharynx, or the epiglottis could be folded down, or the endotracheal tube can become lodged against the edge of vocal cords. These problems can make the passing of an endotracheal tube very difficult. And in addition, ILMA requires a special endotracheal tube which is inconvenient and more costly. One prior art ILMA embodiment, Pagan, U.S. Pat. No. 5,983,897 1999 added a plate projection to the tip of an inflatable balloon to aid insertion. This stiff leading tip increases the risk of soft tissue injury during the insertion. Additionally, the tip projects outwardly from the LMA structure thereby lengthening the device and thereby increasing the difficulty of inserting the device. In the prior art patent U.S. Pat. No. 8,128,071, optical fibers were added to gain visualization of the laryngeal anatomy, but this device also suffers from the limitations stated above.
Prior art also discloses guides for intubation. U.S. Pat. No. 4,832,020, “Tracheal Intubation Guide”, 1989 by Augustine and U.S. Pat. No. 6,672,305 “Shallow Throat Orotracheal Intubation Guide” and RE39,508 E, 2007 “Blind Orolaryngeal and Oroesophageal Guiding Aiming Device” disclose a tracheal intubation guide which sits above the glottis. However, there is no assurance of stable alignment of the device with respect to the laryngeal opening. Therefore, an endotracheal tube can be misguided and cause incorrect intubation and laryngeal trauma.
In another prior art patent by David D. Alfery, U.S. Pat. No. 7,040,312, 2006, “Perilaryngeal Oral Airway” discloses an oral airway that can be used to guide an endotracheal tube into a trachea by axially advancing the endotracheal tube through a gap defined by the material forming the grate of the wedge-shaped housing. But this depends on precisely positioning the wedge shaped housing, that the epiglottis slides up the grate and into abutment with the anterior wall of wedge-shaped housing. These requirements make intubation very difficult to be achieved quickly and reliably.
In another prior art, “Method of manufacturing an airway device”, by Muharmmed Aslam Nasir, U.S. Pat. No. 8,778,248, Jul. 15, 2014, a laryngeal airway device tries to provide a precise mirror image laryngopharyngeal framework, and thus provide an anatomical fit over the laryngeal inlet. However the anatomy of laryngeal pharynx is highly variable and it is very difficult to have an universal device to fit each individual's anatomy. Therefore, a poor air seal is often achieved which easily causes aspiration. Further, if positive ventilation applied, air can easily flow into stomach resulting in artificial ventilation failure and aspiration.
The use of a flexible fiber-optic intubation of the trachea has been used in medical practice for decades which allows for placement of an endotracheal tube with minimal manipulation of the patients airway. While this technique had been considered the gold standard in case of awake intubation, often the tip of the fiber optic scope is touching and bent against the wall of a patient's airway obstructing the view. Additionally, secretions and blood often block the view of the tip of fiber optic scope, all those reasons easily cause the intubation to fail. Further, this technique is time consuming not suitable in emergence situations and requires significant skill and training.
All of these prior art devices have different disadvantages, complications and co-morbidity, and these devices can require significant training and can be expensive to manufacture.
One objective of the various embodiments of this invention is to minimize and mitigate the complication, co-morbidity, and training time for airway devices. Further, it is an objective of embodiments of this invention to provide a new method for vocal cord inspection, biopsy, retrieval of foreign bodies, and use in various otolaryngology.